Using a largescale Fire / Darkness spell against an Undead Dragon.
Fire against a Dragon.
Darkness against Undead.
This complete tard picked the WORST POSSIBLE element choice for this foe, and destroyed everything EXCEPT the target in a fucking mountain range.
Yeah okay, so I guess maybe you might be thinking "fire works against undead", but that is neglecting it being a DRAGON. And darkness was never going to work against either.
Dragon weakness varies with the setting, but usually it is "anything except fire" (though given this is an ascended Skyrim meme, I'm surprised he isn't just shouting at it). Undead weakness is generally Holy / Light.
There is your fucking answer right there: Shout JOOR ZAH FRUL at it.